docs: def setMagnitude(self, band, value):
          """Makes the magnitude of the source in the band equal to value.
          band is a SpectralElement.
          This method is marked for deletion once the .renorm method is
          well tested.
  
          Object returned is a CompositeSourceSpectrum.
  
          .. warning:: DO NOT USED
  
          """
          objectFlux = band.calcTotalFlux(self)
          vegaFlux = band.calcVegaFlux()
          magDiff = -2.5*math.log10(objectFlux/vegaFlux)
          factor = 10**(-0.4*(value - magDiff))
          return self * factor